Sharpening attachment for disk harrows



Sept. 3, 1929. F. M. cAs E SHARPENING ATTACHMENT FOR msx HARROWS Filed Dec. 9, 1925 2 Sheets-Sheet Sept. 3, 1929;

F. M. CASE 1,727,198

SHARPENING ATTACHMENT FOR msx rumnows 2 Sheets-Sheet 2 Filed Dec. 9, 1925 Patented Sept. 3, 1929.

ITED STATES PATENT GFFICE.

FRANCIS 1a. case, or ornvnnann HEIGHTS, 01110, ASSIGNOR, BY MESNE ASSIGN- Mnnrs, r CLAUDE o. HARMON, or CLEVELAND, onro.

SHARPENING ATTACHMENT FOR DISK HARROWS.

Application filed December This invention relates to sharpening attachments for disk harrows and more specifically to a sharpening device adapted to be mounted on the harrow in engagement with a disk to sharpen the same during the operatlon of the harrow.

Gne object or the invention is to provlde a device which may be attached to a disk harrow and which carries a sharpening element which is adjustable so that it may be positioned in engagement with any disk to sharpen the same.

A iurther object is to provide supporting means for the adjustable sharpening element which is adapted to be attached to harrows of various sizes and constructions.

Further objects are to provide means for yieldably holding the sharpening element against the edge of the disk being sharpened and to so mount the sharpening element and yieldable means that the sharpening element can be quickly and easily removed trom one disk and placed in engagement with another.

A further object is to provide a sharpening element which is readily adjustable for engagement with either of two oppositely disposed disks.

A further object is to provide a cutter with a plurality of cut-ting edges, a mountlng for the cutter which will permit the cutter to be quickly adjusted to bring any desired cutting edge into position.

With the above and other objects in view, the invention may be said to comprise the de vice illustrated in the accompanying drawings hereinafter described and particularly set forth in the appended claims, together with such variations and modifications thereof as will be apparent to one skilled in the art to which the invention appertains.

Preference should be had to the accompanying drawings forming a part of this specification in which Fig. 1 is a plan view of a harrow having the sharpener attachment mounted thereon; 2 is a plan view partially in section showing a sharpening element in engagement with a disk; Fig. 3 is a vertical section showing the disk and sharpener in side elevation; Fig. i is an elevation of the cutter carrying arm looking toward the inner face thereof; Fig. is a section taken on line 55 or" Fig. i; Fig. 6 is a section on line 66 of Fig. 4c.

Referring to the accompanying drawing, Fig. 1 shows a common type of disk harrow 9; 1925. Serial No. 74,381.

which. has an angleiron frame and a row of rotatable disks 2, each of which has a hub or spool 3 mounted upon a transverse shaft or axle i. The frame has an. angle iron cross bar, 5 parallel with the row of disks 2 and alongside the peripheries of the disks. The

sharpening attachment is adjustably mounted on the harrow and is supported by bars which extend from the hubs 3 and from the cross bar 5. The inner supporting bars 6 each extend beneath one or the disk hubs 3 and each bar 6 is provided with a clip 7 which extends over the top of the hub and supports the inner end of the bar from the hub. To enable the bar 6 to be attached to harrows of different sizes the clip 7 is adjustable longitudinally of the bar 6 being attached thereto by a bolt 8 which extends through a long slot 9 in the bar 6. The outer end of the bar 6 has a transversely channeled head 10 which receives the web of a T bar 11 which extends parallel of the cross bar 5 on the inner side thereof adjacent the peripheries of the disks 2 the T bar 11. being secured within the channel of the bar 6 by means of set screws 12. Channel shaped brackets 13 are secured to the web of the T bar 11 by means of set screws 14 and each of these brackets is provided with an arcuate T shaped rib 15 upon which is adjustably secured an outwardly extending bar 16 which has a chan nel head 17 which fits upon the rib 15. The bars 16 may be adjusted to different angular positions with respect to the bracket 13 by sliding the heads 17 along the arcuate guide ribs 15 and may be secured in adjusted positions by set screws 18. The arms 16 extend outwardly beneath the cross bar 5 and each arm carries a hook 19 which has a threaded stern 19 adapted to extend through any one of the longitudinal row of holes 20 in the bar 16 and which receives-a nut 19 which engages the under side of the bar 16 to draw the hook into engagement with the cross bar 5 and clamp the same between the hook and supporting bar 16. The angularly'adjustable bars 16 provide means for supporting the T bar 11 at various elevations with respect to the cross bar 5, and the adjustably mounted hooks 19 permit the bars 16 to be attached to frame cross bars which are located at different distances from the peripheries of the disks. Also by adjusting the clip 7 and the hook 19 the T bar 11 may be adjusted toward or from the peripheries of the disks 2 to properly position the bar with respect to the disks.

The T bar 11, which is positioned with its head uppermost and in a horizontal position alongside the peripheries of the disks, serves as a guide bar along which the sharpening element may be adjusted for engagement with any disk in the row. Slidably mounted upon the head of the T bar 11 there is a supporting member 21 whichhas a base portion 22 which rests upon the top of the head and which has depending inturned flanges 23., which extend beneath the flanges of the '1' bar to retain the supporting member in place thereon. The supporting member 21 has a side plate 24 which extends outwardly from the outer side thereof and which is bent inwardly at the upper end to provide a bearing portion 25 parallel with the base portion 22. The supporting member 21 may be rigidly secured in any adjusted position along the length of the T bar 11 by means of a combined pintle and retaining bolt 26 which eX- tends through the upper bearing portion and is screwed into a threaded opening through the base portion 22. The belt 26 can be screwed into the base portion to bring the lower end thereof into engagement with the top of the T bar 11 to draw the flanges 23 into tight engagement with the under side of the flanges of the T bar to lock the supporting member against movement along the T bar. The sharpening tool is pivotally mounted on the vertical pintle 26 between the base 21 and the bearing portion 25 of the supporting member. The sl'iarpening tool is provided with an arm 27 which has an inwardly opening channel formed in the outer end thereof in which is mounted a bearing roller 29 which is adapted to engage with a side face of a disk. The arm 27 has an inner forked end. 30 within which is mounted the inner end portion of a cutter carrying arm 31 the arms 27 and 31 being pivotally connected by means of a sleeve pintle 32 which extends through the forks of the arm 27 and through the inner end of a cutter carrying arm 31 which fits within the forks 30. The cutter carrying arm 31 has a widened outer end portion 33 which is provided upon its inner face with intersecting angularly disposed channels in one of which there may be mounted a sharpening element in the form of a cutter bar 35 which is substantially square in cross section and which has sides 36 which are slightly concave providing a cutting edge 37 at each of the four corners of the bar. When the cutter bar 35 is mounted in a channel 34 the inner side of the bar projects beyond the inner face of the portion 33 of the supporting arm so that it may engage with the edge of a disk. As shown in Fig. 5 the bottoms of the channels 34 are inclined with respect to the inner face of the portion 33 of the arm so that the cutter bar is supported with its cutting edge projecting inwardly beyond the edge at the opposite side of the bar. The cutter bar 35 is held in place by means of an eye bolt 38 which has a circular eye 39 through which the cutter bar 35 extends. The eye bolt 38 is located at the intersection of the angularly disposed channels 34 and has a threaded stem 40 which extends through a tapered opening 41 at the outer side of the cutter arm 31. At the outer end of the opening 41 a rounded seat 42 is pro- -vided in which a rounded washer 43 fits. The stem 40 extends through the washer 43 and has a nut 44 which bears against the washer 43.

The cutter bar 35 can be adjusted longitudinally to bring different portions of a cutting edge into engagement with a disk loosening the nut 44 sutliciently to permit the cutter bar to be slid through the eye 39. The cutter bar 35 can be adjusted to bring any desired cutting edge into disk engaging position by loosening the nut 44 sufficiently to permit the bar 35 to be freed from its channel so that it can be rotated in the eye 39. l/Vhen the eye bolt is loosened sufficiently to free the cutter bar from the channel in which it is held the eye bolt can be shifted to position the bar in either one of the angular-1y disposed channels 34 so that the inclination of the cutting edge can be reversed when desired.

At the inner end thereof the cutter supporting arm 31 has an integral projection 45 which projects beyond the outer side of the roller carrying arm 27 and the arm 27 is provided adjacent its outer end with an integral outwardly projecting lug 46. A threaded rod is screwed into a threaded opening in the lug 46 and is rigidly secured to the lug 46 by means of a lock nut 48 which engages with the inner face of the lug 46. The rod 47 extends substantially parallel with the arm 27 and through an opening in the extension 45, the opening in the extension 45 being of greater diameter than the rod 47 to permit pivotal movement of the arms 27 and 31. The rod 47 has a wing nut 49 thereon which is adapted to be screwed into engagement with i the outer face of the extension 45 to force'the extension 45 inwardly to cause the cutter carrying arm 31, with which the extension 45 is integral to swing outwardly away from the arm 27. A coil spring 50 surrounds the rod 47 and bears at one end upon the inner face of the extension 45 and at the other against a nut 51 on the threaded rod 47.

When the nut 49' is adjusted to a position out of engagement with the extension 45 the spring 50 acts to press the arm 31 toward the arm 27 serving, when the sharpening element is in engagement with avdisk as shown in Fig. 2, to yieldingly press the cutter against theedge of the disk. The tension of the spring 50 may be varied by adjusting the nut 51 and the arms 31 and 27 can be forcibly spread apart in opposition to the spring 50 by screwing the nut 49 against the outer face of the extension 45.

In applying the sharpening attachment to a harrow the supporting members 6 and 16 are adjusted to position the T shaped guide bar 11 parallel with a row of disks and at the proper distance from the peripheries thereof. To engage the sharpening element with a disk, the wing nut 49 is screwed down against the extension 45 to hold the arms 27 and 31 far enough apart to permit the cutter and roller 29 to be moved to positions on opposite sides of the disk as the supporting member 21 is moved along the guide bar 11. When the supporting member 21 has been adjusted to the proper position with the arms 31 and 27 positioned with the cutter bar 35 and roller 29 on. opposite sides of the disk 2, the pintle bolt 26 is tightened to rigidly secure the supporting member in place and the wing nut 49 is then loosened to permit the spring 50 to swing the arms 27 and 31 toward each other causing the roller 29 to engage a face of the disk and the cutter bar 35 to engage the beveled edge of the disk, the disk being yieldably gripped between the roller 29 and cutter bar 35 so that during the rotation of the disk the cutter bar 35 will act upon the beveled edge thereof. WVhen it is desired to shift the sharpening element from one disk to another the wing nut 49 is screwed down against the extension 45 to spread the arms 27 and 31 sufiiciently to permit these arms to be moved out of engagement with the disk whereupon the supporting member 25 may be adjusted to a position adjacent the next disk to be sharpened.

The harrow disks are usually dished or concaved and the disks may be mounted in one gang with their concave sides facing one way and in another with their concave sides facing the other way. In order to enable the sharpening element to act upon disks facing in either direction the sharpening tool which includes the cutter and roller carrying arms is in the form of a unit detachable from the supporting member, and, by removing the pintle bolt 26 these arms may be removed and reinserted in the supporting member in re versed position. The reversing of the arms would also reverse the inclination of the cutter and for this reason the two angularly disposed channels 34 are provided permitting the inclination of the cutter bar to be reversed so that the cutter bar may be positioned properly for engagement with disks facing in either direction.

Having described my invention, what I claim is:

1. The combination with a harrow having a row of disks, of a T-shaped guide bar extending alongside the row of disks, supporting bars for said guide bar extending transversely thereof and having means for attachment to parts of the harrow and to the web of the T-shaped guide bar, said attaching means being adjustable to permit said supporting bars to be attached to harrows of dif ferent sizes, and a sharpening tool slidably mounted on the head of the guide bar for adjustment longitudinally thereof.

2. The combination with a harrow having a frame and a row of disks rotatably mounted in' the frame, of a plurality of supporting bars, certain of said bars being detachably and adjustably secured to the harrow adjacent the axis of the disl' s and others to a portion of the frame outside the periphery of the disk, a guide bar carried by the supporting bars and extending transversely thereof adjacent the peripheries of the disks, and a sharpening tool adjustable longitudinally of the guide bar past said supporting bars for engagement with any one of the disks.

3. The combination with a harrow having a frame and a row of disks rotatably mounted in the frame, of a plurality of supporting bars, means adjustable longitudinally of certain of the bars for securing the same to tho harrow adjacent the axis of a disk, means adjustable longitudinally with respect to other of the bars for securing the same to a portion of the frame beyond the peripheries of the disks, a guide bar supported by said support ing bars and extending adjacent the peripheries of the disks, and a sharpening tool carried by the guide bar and adjustable longitudinally thereof past said supporting bars.

4. A disk sharpening attachment comprising a pair of pivotally connected arms, a sharpening element having a cutting edge and clamped to the inner face of one of the arms, said sharpening element being mounted for adjustment to different angular positions upon the inner face of said arm, a roller mounted upon the opposite arm and projecting beyond the inner face thereof, and a spring acting upon the arms to press one toward the other.

5. A disk sharpening attachment comprising a supporting member adapted to be mounted adj acent the periphery of a disk, a pair of arms, onecarrying a sharpening element engageable with an edge of the disk and the other a roller engageable with a face of the disk, a hollow pintle connecting the arms, a spring carried by the arms and acting to move the arms together to yieldingly grip the disk between the roller and sharpening element, and a removable pintle extending through the tubular pintle for pivotally and detachably securing the arms to the supporting member.

6. In a disk sharpening attachment, a sharpening element in the form of a cutter bar substantially square in cross section and having a cutting edge at each of the four corners, a holder for said cutter bar having a channel to receive the cutter bar, the bottom of said channel being transversely inclined with respect to the race vof the holder and means for releasably holding the cutter bar in the channel.

7. In a disk sharpening attachment, a cutter bar, a holder for the cutter bar having intersecting angularly disposed channels each adapted to receive the cutter bar, and an eye bolt by which the cutter may be clamped in either of the channels, said eye bolt being at the intersection of the channels and the eye of said bolt extending around the cutter bar.

8. In a disk sharpening attachment, a hold er having a channel extending across the face thereof, a cutter bar adapted to fit in said channel, said cutter bar being substantially square in cross section, and means for securing said cutter in the channel of the holder comprising an eye bolt having an eye through which the cutter bar passes and in which said cutter bar can turn when said eye bolt is loosened.

9. The combination with a barrow having a row of disks, of a disk sharpening attachment comprising a guide bar mounted adja cent the peripheries of the disks, a supporting member slidably mounted on said guide bar and adapted to be secured in any position 10. The combination of a harrow having a row of disks, of a disk sharpening attachment comprising a guide bar mounted adjacent the peripheries of the disks, a supporting member slidably mounted on said guide bar and adapted to be secured in any position to which it may be adjusted thereon, an arm pivotally and reversibly connected to said supporting member and adapted to swing toward and from the periphery of the disk, means for yieldably pressing said arm toward the disk, a cutting element mounted on the inner face of said arm and means for securing the cutting element to the arm in reversed angular positions with respect thereo.

In testimony whereof, I hereunto afiix my signature.

FRANCIS M. CASE. 

